1. Field of the Invention
The present invention relates generally to latching devices and more particularly to latches which are operable through slam-action closing and rotational opening to secure a first member, such as a door or panel, in a closed position relative to a second member, such as a frame or cabinet.
2. Background of the Invention
Presently, there are a number of pawl assemblies known in the art which are operable by rotation of a shaft or the like for securing panels together or against a corresponding frame. Generally, fasteners of this type include a latching pawl which is provided extending from a shaft disposed in a latch housing. In operation, rotation of the shaft corresponds with a movement of the latching pawl to its latched position. Generally, the fasteners of this type require varying degrees of rotation of the shaft for operation of the latch. These latches include one or more fixed members, such as a housing, which is mounted to a panel, and also include movable members which are rotatably provided to turn relative to a fixed member.
One type of latch is a "quarter turn" fastener which requires a 90.degree. rotation for operation. Such latches usually consist of a housing, drive stud, spring and pawl which are installed within an aperture formed in a door panel. However, one problem with such prior art designs is that water, dust and other matter is able to pass freely through the latch and into the interior compartment of the door panel, thus into contact with the contents contained therein. Another problem is that the spring which is positioned proximate the top of the latch between the drive stud and the housing is required during operation to support the load which is being applied by the latch. This increased stress applied by the latch adversely affects the spring's operation and durability.
Furthermore, the designs which have been developed in order to hasten the installation process have proven to adversely affect latch operation. In particular, some designs allow a mounting nut to be slid over the pawl and onto the housing in order to accommodate installation within a panel aperture. However, these prior art designs require either a necked down section in the pawl, which reduces the strength of the pawl, or an extra loop in the pawl, which is rather difficult to manufacture. These prior art latches generally include several components which must be assembled and installed on a panel. In some cases, prior art type latches include components which must be installed on the panel, and then other components which must be installed on the panel mounted components. The need exists for a latch which can be resistant to debris and dust, and can be readily installed on a panel for operation.
A rotating pawl latch, where a pawl is rotated to one location to close the latch and to another location for releasing the latch are known. However, with such a prior art device, slam latching is not provided, rather, the pawl must be returned to its original position by further rotation by the user. In instances, such as the examples referred to above, multiple components are required to regulate the movement of the pawl among latching and releasing positions. In industries, such as, automotive assembly operations, the ease with which latch installation can be accomplished is important. For example, hinged panel, as well as lift-off panel applications are common uses in the automotive industry where slam latches are employed. The panels to be latched, for example, can include closure panels of storage compartments, as well as mechanical panels to regulate access to engines, and other mechanical systems.
In addition, many latches require precise alignment so that a pawl can engage a keeper and maintain the latch against being inadvertently opened or unsecured. For example, in conditions where wear and tear on adjacent panel members creates gaps or misalignment between the panels, often a keeper must be reinstalled for proper positioning or the panel replaced. Furthermore, where temperature changes occur, such as extreme hot and cold due to sunlight exposure, or changes in environmental temperatures, panels may tend to misalign. Furthermore, a panel may bear the load from a weight or object upon it and can buckle or bend, also affecting the panel alignment. A need therefore exists, for a latch which can be installed in a panel and can facilitate maintaining the latch in a secured relation with a keeper over a range of positions, for example if a panel becomes misaligned.
The present invention attempts to provide a latch which is an improvement over prior latch designs, and which provides features of slam action and spring return of the pawl member, and, further, which can be readily mounted to a panel.